Analyze ZIP file structure, compression ratios, and duplicate files. Find ways to optimize your ZIP archives locally in browser. Free and private.
Drop your ZIP file into the local analyzer zone.
Explore the detailed files, compression statistics, and metadata table.
Download the audit report or view full integrity results.
Your data is processed entirely inside your browser using client-side JavaScript. Nothing ever travels over a network to any server — making BunchTool the most private option available.
Because everything runs locally in your browser, there are no upload queues or server wait times. Results appear in seconds regardless of your internet speed — or even without any connection at all.
Inspect compression algorithms, file count distributions, dates, and header sizes to audit the health and layout of any ZIP.